<div id='editor'>
	<p>Foo</p>
	<h1>Bar</h1>
	<h2>Baz</h2>
	<h1>Test</h1>
	<p>World</p>
</div>

<script>
	CKEDITOR.replace('editor', {
		allowedContent: {
			$1: {
				elements: CKEDITOR.dtd,
				attributes: true,
				styles: true,
				classes: true
			}
		},
		disallowedContent: 'h1{text-align}'
	});
</script>
